1,5-Diaminopentane (frequently also referred to as pentamethylenediamine or cadaverine; referred to as DAP hereinbelow) is an important raw material in the chemical industry. DAP is used, for example, in the preparation of polyamides, polyureas or polyurethanes and of copolymers thereof.
Moreover, the fermentative or enzymatic production of DAP via lysine decarboxylation has been known for some time. Various processes for isolating the product of interest from the fermentation broth have been described in this context.
EP-A-1 482 055, for example, describes the enzymatic decarboxylation of lysine in the presence of a dicarboxylic acid for adjusting the pH during the reaction. The DAP dicarboxylate produced in the process is isolated by firstly decolorizing and concentrating the solution comprising the product of interest and then crystallizing DAP dicarboxylate in a cooling crystallization process.
WO-A-2006/123778 describes the preparation of DAP carbonate by enzymatic decarboxylation of lysine in the presence of carbon dioxide. DAP is formed by concentrating the reaction solution and eliminating carbon dioxide.
JP 2004-208 646 describes the preparation of DAP dicarboxylate by enzymatic decarboxylation of a solution comprising L-lysine dicarboxylate and precipitation of DAP dicarboxylate by adding an organic solvent selected from among alcohols, ketones and nitriles.
JP 2004-222 569 describes the preparation of DAP by employing a coryneform bacterium expressing L-lysine decarboxylase, adjusting the culture supernatant to pH 12 and extracting DAP with a polar organic solvent.
Finally, JP 2004-000 114 describes the preparation of DAP by converting highly concentrated L-lysine monohydrochloride using E. coli cells expressing L-lysine decarboxylase, adjusting the reaction solution to pH and extracting the reaction product with a polar organic solvent followed by distillation.
However, the prior art processes based on DAP extraction with the aid of an organic solvent are particularly disadvantageous in that the yield of product of interest is suboptimal and the extraction step in particular is too slow and the overall process is too time-consuming, this being greatly disadvantageous to applying said preparation on an industrial scale.